Reactor worker speaks out 50 years after meltdown

John Pace Fifty years ago, a nuclear reactor in the hills above Simi at the Santa Susana Field Laboratory suffered a partial meltdown.

For 20 years, that accident remained hidden from public knowledge. While the meltdown at the Sodium Reactor Experiment (SRE) is no longer a secret, many residents in Simi and Los Angeles still are not aware of exactly what happened on top of the hill July 13, 1959.

One reactor worker—who was just 20 years old and training to become an atomic reactor operator at the time of the accident—came forward last week on the 50th anniversary of the meltdown to share his experience.

Talking to a living room filled with reporters who had gathered at a Santa Susana Knolls home just below the field lab, John Pace, now 70, told what he remembers of the days following the nation's first nuclear meltdown.

Pace worked the shift after the accident. When he came into the building, he could feel the tension in the air. As he listened to his co-workers, he learned there had been a power excursion, or surge, and that operators were barely able to shut the reactor down.

Radioactivity levels during the accident went off the scale because they were "hotter" than instruments could measure. Pace, who'd been on the job only four months, said his co-workers were fearful of where the radiation was headed.

"The men that were working on the earlier shift were very worried because of the direction the wind was blowing," said Pace, a Moorpark resident in 1959 who now lives in Idaho. "All these men lived in the west end of the San Fernando Valley and it went right over their homes. It went right over their families, their children."

About five weeks after the accident, the Atomic Energy Commission sent out a press release stating that "a parted fuel element had been observed," but there were no radioactive releases or evidence of unsafe operating conditions.

The truth came out in 1979, however, when UCLA students found commission records of the accident and released them to the media.

"This was one of the most serious accidents in nuclear history to date, and it was kept secret for two decades. Half a century later, we're still trying to clean up the mess at the site," said Dan Hirsch, president of Committee to Bridge the Gap, which had a hand in letting the public know about the accident 30 years ago. "It's a powerful lesson of how things can go badly wrong with this technology."

The reactor used liquid sodium as its coolant; most commercial reactors today use water. Sodium burns in air and explodes in water, so it must be kept isolated from both. Because of the danger, the pumps that brought the sodium into the core had to be cooled with tetralin, an organic coolant.

But tetralin managed to leak into the sodium coolant through a small crack, forming a sticky mixture that clogged the fuel's coolant channels. Thirteen of the reactor's 43 uranium fuel elements became overheated and melted, which lead to the power surge.

Despite their inability to figure out what went wrong, Pace said, workers on his shift started up the reactor again just a few hours later. It ran for two more weeks, during which time radioactive gases were pumped into tanks and then vented into the atmosphere.

"Each time they started and stopped the reactor . . . radiation from the reactor was released," he said.

After the meltdown, Pace said he helped scrub the floors and walls clean of contamination, wearing only cotton coveralls for protection. He said workers eventually switched to using Kotex sanitary napkins as sponges, which absorbed the contamination better and could be thrown away.

During the cleanup, workers were not allowed to wear the film badges that measured a person's radiation exposure because the amount of radiation would be higher than the allowable limit, he said.

The reactor was finally shut down July 26 and Pace helped with the physical inspection of the reactor, including pulling out damaged fuel rods. At one point, a fuel rod broke and a panicked operator mistakenly pushed a button that lifted the lead shield of the reactor and exposed the whole building and employees to radiation.

Though he knew the dangers of the job, Pace said he didn't realize the full implications of his time spent at the SRE until later on in life—especially after more information on the accident became public in the 1980s and his health started to deteriorate.

"I still have trouble to this day with my lungs. I have to keep a watch on perfume or smoking. I can't be around anything with chemicals, like cleaning chemicals," he said.

Known as "the kid" around the SRE, Pace said he's one of the last workers still living and he feels a responsibility to speak out about the meltdown, the ramifications of which are still not completely known.

"I want to let people know what actually happened and the exposure we were around," he said. "It was some very dangerous operations as we were trying to repair the reactor."

Today, the cleanup at the field lab continues. According to Hirsch, more than $250 million has been spent on these efforts.

Most recently, the Department of Energy gave the U.S. Environmental Protection Agency $40 million to complete a radiological survey of Area IV.